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By Dharmil Patel, Michael J. Chow

"Construction progress is nearing completion at a Brownfield Site for a 100,000sf mixed-use 10 story building plus cellar for Silver Star Motors including a two-floor pre-owned Mercedes Benz showroom; high-end residential rental studios, 1, 2, and 3 bedroom apartments; and penthouses on the upper two floors. Excavation through impacted soil extended to 15ft depth. Project is approximately 7 ft north of a NYCT subway station, portions of the SOE are within inches of a 6ft diameter NYCDEP Sewer, and cellar extends below the depth of adjacent structures, requiring over 200 lf of underpinning.A complex series of earth retention systems was utilized consisting of underpinning, drilled-in soldier piles (micro-piles), timber/concrete lagging, soil anchors and inclined rakers supported by a partially constructed foundation mat. Foundation mat subgrade was approximately 4 ft below the groundwater level creating more challenges during underpinning and achieving suitable foundation subgrades. All construction was undertaken on a non-union basis.This paper describes the design, construction, and lessons learned for the multiple earth retention systems, Brownfield Remediation requirements, instrumentation, and monitoring used to manage complications of building adjacent to an active subway station, in close proximity to existing utilities, with underpinning and mat foundation installation below the water table.Results of the instrumentation program are summarized which utilized an AMTS, monitoring prisms on adjacent structures, automated seismographs, and manual NYCT surveys."

Jan 1, 2016

By Prasanta Paul, Aminul Islam

"Nhava Sheva (India) Gateway Terminal Private Limited proposed to construct a container terminal yard, comprising a back-up area at Jawaharlal Nehru Port Terminal (JNPT), Uran, Maharashtra. The proposed container terminal yard is located on a recent reclamation on the Thane Creek, which was developed by land-based reclamation method. The underneath soft marine clay was treated, using vertical band drains and placement of surcharge upon.Settlement of the reclamation during its construction was monitored using settlement plate installed at +4.8m CD elevation which was above the highest high water level.This paper examines the settlement behaviour of the reclamation during the ground improvement works. The geotechnical parameters are back-analyzed by the authors from the field settlement results and the concerned preloading details. The back analyzed coefficients of consolidation due to horizontal flow (Ch) are compared with laboratory determined parameters and the estimated value, using Asaoka Method (1978). The authors also studied field compression ratio [CR= Cc/(1+e0)] vs. the compression ratio determined by laboratory test using back-analysis method.1. INTRODUCTIONNhava Sheva (India) Gateway Terminal Private Limited proposed to construct a container terminal yard, comprising a back-up area of approximately 27 hectares, complete with associated buildings and services on a part brownfield/ greenfield site. The back-up area shall include a heavy duty block paved pavement with band beams for electric Rubber-Tyred Gantry Crane (eRTGC) alongwith surface water drainage system and other services including area lighting, provision of fire-fighting facilities , sources for potable water and power.Based on the Employer’s Requirement and the available geotechnical investigation report, ground improvement scheme is designed by the construction contractor. Ground improvement works included the installation of prefabricated vertical drains and subsequent placement of surcharge for accelerating the consolidation of the underlying soft marine clay."

Jan 1, 2015

By Edward Jacobsen

The Oak Creek Power Plant in Oak Creek, Wisconsin is currently undertaking an expansion project. In order to supply cooling water to this facility, a 27' (8.2m) diameter tunnel will be bored, in rock; to connect to 4 vertical Intake shafts located approximately 1.5 miles (2.4km) offshore in Lake Michigan. In 2004, Case Foundation Company was awarded a lump sum contract to Install these intake shafts. When complete, the plant is expected to circulate upward of 2 billion gallons per day (7.5 billion liters) through this system. Two shafts were drilled in a (shortened) construction season in 2005 and the remaining 2 shafts and 4 liner assemblies were completed in 2006. Future connection to the tunnel, in 2007, will be accomplished by mining upward to reach the lower portion of each liner and then removing its internal bulkheads to permit the flow of the lake water into the tunnel.

May 11, 2007

By Arash Saeidi-Rashk-Olia, Dunja Peric

Energy piles are gaining increased popularity due to a growing demand for clean energy. To further advance the understanding of soil-structure interaction in energy piles, recently-derived analytical solutions have been implemented to investigate the impact of stratigraphy on the soil-structure interaction. This was accomplished by comparing the measured and predicted head displacements, axial strains and stresses in an energy pile embedded in the actual homogeneous and layered soil profiles, as well as into synthetic homogeneous soil profiles. The analytical solutions for homogeneous soil profile captured the smooth experimentally observed response versus depth very well. In the case of a layered soil profile, the corresponding analytical model was capable of capturing nuances in trends of axial stress and strain versus depth at the interface of different layers. The analytical predictions for the layered profile appear to be slightly less accurate than for the homogenous profile. The experimental data obtained from the layered profile appear to be a bit more scattered than those from the homogeneous profile. In the former case, the interplay of the individual soil layers with the pile occurs while maintaining the continuity of the pile stress and displacement at the interface of different layers. The response throughout each layer of the layered profile is quantitatively different than the corresponding homogeneous response. Nevertheless, qualitatively the response throughout each layer of the layered profile is similar to the response of the pile embedded in the corresponding homogeneous layer.

Sep 8, 2021

By Christian B. Woods, Joe C. Drumheller

"Kenneth A. Huber, P.E., Langan Engineering & Environmental Services, New York, New York, USAThe dream to bring New Jersey Devils hockey to the largest city in New Jersey became a reality in the summer of 2005, when construction began for the Prudential Center in downtown Newark. The Prudential Center site encompasses an entire city block that had a varied history of uses ranging from a cemetery in the late 18th century, to a rail yard and train station for the now-defunct Central Jersey Rail Road in the 19th and early 20th centuries, to commercial development in the latter half of the 20th century. Each of these prior uses presented challenges to the design and construction of the Prudential Center that required innovative engineering solutions, including: archaeological investigation and exhumation of the former cemetery occupants, protection of historic buildings surrounding the site, and extensive demolition to remove old train bridge foundations.The design team was required to develop potential foundation systems for the arena. Several foundation concepts were evaluated for cost and constructability, including: driven piles, drilled shafts, and shallow foundations on improved subgrade. Following a detailed cost analysis and value engineering exercise, the decision was made to support the arena on spread footings following the completion of a multi-phased ground improvement program consisting of a combination of dynamic compaction and removal and replacement. To evaluate achievable allowable bearing pressure as part of the design, a dynamic compaction test section was performed within the building footprint prior to the start of production work; this resulted in an increase of the allowable design bearing pressure from 2 tons per square foot (tsf) to 3 tsf. This reduced the expected foundation costs by 30% and gained sufficient time in the schedule to allow for the completion of the arena in time for the New Jersey Devils 2007- 2008 hockey season.BACKGROUNDThe dream to bring New Jersey Devils hockey to the largest city in New Jersey became a reality in the summer of 2005, when construction began for the Prudential Center in downtown Newark. After several years of negotiating between the City of Newark, local landowners, area developers, and the Devils themselves, a deal was finally struck to erect Newark Arena, now known as the Prudential Center, right next to City Hall. This is not to say, however, that once the site location was finalized, that no further challenges were encountered in the construction of Newark’s new crown jewel."

Jan 1, 2015

By Jun Ohbayashi, Yoshiyuki Yagiura, Hiroaki Miyatake, Masuo Kondoh, Naotoshi Shinkawa

"Reducing the improvement ratio of ground improvement is an extremely efficient way to reduce the construction cost and construction period of mitigation measures for soft ground. The Arch Action Low Improvement Ratio Cement Column (ALiCC Method) is one method for this, and it is being increasingly applied to sites. This method enables us to rationally evaluate the embankment loads that are acting on cement improved soil columns and unimproved ground, by considering the arch action generated in the embankments and from there thusly allocate improved soil columns in spans of a greater distance than those needed for conventional methods. As a result, it serves to reduce construction costs and the construction period, while also minimizing the settling of the embankment and differential settlement, by placing numerous improved soil columns in the ground immediately beneath the embankment at equidistant intervals. In this report, we give a basic overview of the ALiCC Method, report typical construction results from real life cases that have been carried out, and make comparisons with other construction methods in order to report on the effectiveness of this design method.OVERVIEW OF ARCH ACTION LOW IMPROVEMENT RATIO CEMENT COLUMN (ALiCC) METHODIn the area of mitigation measures for soft ground, a significant role is played by ground improvements using improved materials such as cement. For this reason, a reduction in construction costs and construction period required for ground improvements has become of greater importance. The Public Works Research Institute carried out joint research with Kiso-Jiban Consultants Co. Ltd., Kitac Co. Ltd., and Fudo Tetra Co. Ltd. over a period from 1998 through 2002, and, from that, developed the ""Arch Action Low Improvement Ratio Cement Column Method"" (hereinafter referred to as the ""ALiCC Method"") that enables ground improvement with a lower improvement ratio (the improved area ratio is approx. 10% to 30%) than is required for conventional methods, while also ensuring stabilization and minimizing the settling of embankments.In the area of mitigation methods for soft ground by deep mixing, the dominant method until now has been that (50% or more of improvement ratio) shown in Fig. 1. This method comprehensively improves the area under the face of the slopes of both sides of the embankment. This is based on the calculated stability against rotational slip, which states, ""the most effective way to ensure the stabilization of the embankment environment is to carry out improvements of the area under the face of the slope."" Therefore, for the area under the face of the slope, ground improvement by deep mixing was done, and for the soft ground in the area under the middle part of the embankment, accelerated consolidation methods (hereinafter referred to as ""conventional method"") such as sand draining method and paper draining method were used. Mitigation measures that combine these improvement methods have also been mainstream for a long period of time and are used to prevent side deformation around the embankment. However, there have been some problems that have occurred, such as a situation where consolidation settling occurs in the center area under the embankment where no improvement had been carried out. This phenomenon leads to a situation in which the improved soil columns in the area under the face the of slope are pushed to the outside, which results in side deformation occurring around the area of the embankment, and additionally the occurrence of a step due to a situation of differential settlement between the improved ground and the consolidation advancing part, which results in cracks in the embankment."

Jan 1, 2015

By Rick Deschamps

A reoccurring problem with support of excavations in urban areas involves the placement of external support components like anchors or nails in right-a-ways, subway and utility setbacks, in areas occupied by adjacent structures, and within the property of non cooperative neighbors. Such a situation occurred for a project in Arlington, Virginia, which ultimately resulted in the preliminary design of a large footing supported cantilever retaining wall that was extremely costly and impractical to build. An innovative design alternate consisting of a series of vertical concrete elements (VCEs) supported by post tensioned tiedowns was proposed to the General Contractor and accepted by the owner. The VCEs were designed to serve as the main structural elements for both the temporary support of excavation system and the permanent wall. The VCE?s were constructed using single bite diaphragm wall panels oriented perpendicular to the excavation face including a rebar cage and tremie concrete. Threaded inserts were placed within the rebar cage to attach the cast in place exterior wall. Overall stability and lateral movement of the VCEs were controlled by high capacity vertical anchors embedded within the VCE. A detailed instrumentation program was installed to monitor the movements of the VCEs with relation to the excavation depth. The paper present the project case history by discussing the design concepts of the VCE, the construction approaches used to install them, the construction challenges encountered, and the performance of the unique system.

Jan 1, 2008

By Hyun. I. Park

Although numerous investigations have been performed over the years to predict the behavior and bearing capacity of piles, the mechanisms of these behavior and bearing capacity of piles have yet to be entirely understood. Bearing capacity is difficult to predict, because it is affected by many parameters, which have complex relationship with each other. The present paper describes the application of Artificial Neural Network (ANN) in dynamic load tests to predict the resistance of driven piles. The tip, shaft, and total pile resistances can be predicted only for piles with available corresponding measurements of these values. The design methodology composed of ANN and genetic algorithm (GA) is applied to find the optimal neural network model to predict pile resistance. The results of this study indicate that the neural network model serves as a reliable and simple tool for predicting the capacity of driven piles.

Jan 1, 2006

By Ken MacLeod

A development at 83 Queens Road in Melbourne, Australia required construction of a three level basement. The normal geotechnical constraints of excavating adjacent to an existing relatively new building were challenging enough for the complicated soils profile occurring at the site. An additional significant challenge faced by the designers, was the requirement to excavate underneath the entire footprint of an existing heritage listed building, known locally as the Mansion, in the centre of the site. Maintaining the structural integrity of that building was afforded the highest priority during the 10m excavation. This paper describes geotechnical aspects of the analysis, design and construction of the secant retention system adjacent the new building and support of the Mansion enabling the 10m excavation to proceed without causing damage to the structure. The secant wall comprised hard-soft interlocking piles constructed using CFA methods. CFA piles along the length of the Mansion provided short term support, with the building load being transferred to the piles by large steel beams jacked under the building. Survey results confirmed that movements of the retaining wall and also the load bearing piles were minimal and well within design expectations.

Jan 1, 2006

By Theodore von Rosenvinge

Large diameter (2.4 meter) drilled shaft foundations were installed to depths of over 62 meters through soil into Arkose bedrock for Connecticut?s Pearl Harbor Memorial Bridge (I-95 over New Haven Harbor). The project involved many ?firsts? including the first ?extradosed? cable-stayed bridge in the US, and for Connecticut, the deepest drilled shafts, the first use of a rotator to install shaft casing, and the first use of the Mini-Sid technology for rock socket bottom inspection. Design utilized both friction and end bearing for rock sockets. O-Cell testing was employed to maximize performance factors during design and to allow adjustments to socket lengths during construction. Favorable test results permitted a reduction in socket lengths and significant cost saving.

Jan 1, 2011

By Seth H. Hamblin, John E. Regan, Dimitrios Palantzas

"Through reliability-based calibration of larger pile load test databases, recent developments of the Load Resistance Factor Design (LRFD) methods, which include geotechnical load and resistance factors for deep foundations design, have advanced the state of practice for geotechnical engineering. These load test databases upon which the current geotechnical load and resistance factors have been developed are limited, however, and do not provide sufficient data to support the development of resistance factors for uplift (tension) pile capacity. As such, some recommended resistance factors for uplift capacity estimation methods are simply derived by reducing the recommended resistance factors for piles in compression by a factor of 0.10.The results of three (3) tension loading tests performed to failure on 508 mm (20- in) square precast, prestressed concrete piles, driven though granular soil in southeastern Massachusetts, are presented and compared to static pile capacity calculations and dynamic analyses performed using the Pile Driving Analyzer (PDA) during installation. These results are presented along with current recommended LRFD resistance factors for driven piles under uplift (tension) loading conditions. These comparisons offer an assessment of the applicability and limitations of current resistance factors methods for piles under uplift loading and may be useful additions to the existing database for future calibrations of LRFD resistance factors for driven prestressed concrete piles in sand.IntroductionIn 2010, two (2) natural draft cooling towers were constructed by Kiewit (Kiewit) Construction Company of Woodcliff Lake, New Jersey at the Brayton Point Power Station in Somerset, Massachusetts. These massive 500 foot tall, 400 foot diameter cooling towers were designed to convert the existing “open loop” system into a “closed loop system” thereby dramatically reducing the thermal impact to Mt. Hope Bay.Based on design guidance from the German VBG Design Code and the Massachusetts State Building Code (MSBC), tension (i.e. uplift) and lateral loads due to wind loads and design seismic events represented the critical loading conditions.Weighing approximately 190,000 kips upon completion, the cooling tower loads are transferred to 44 foundation nodes (i.e. pile caps) evenly spaced along ring beams which run the circular perimeter of each tower base. Each pile cap node was designed to resist a 2,000 ton compression load, 200 tons in tension (i.e. uplift), and 600 tons in the lateral direction."

Jan 1, 2015

By Allen Cadden

The type of soil we had was a silty fine sand. It had been placed by hydraulic methods in 1904 so it was quite clean I would say less than 10% silt the rest of it was very loose sand. That I'm not certain, I've only done it on sandy soils but it would stand to reason that some sort of a number should apply because you are measuring the amount of work that you are doing to it so if the soil is fairly consistent over the site it should be able to generalize from there but I don't know for a fact that it works. Well, verifying to ourselves that this method actually worked because we weren't certain at first when we were doing it so then we would develop the numbers and then check the results.

Feb 10, 2003

By Vijaya Bhushan Rao, Jason Redgers

The typical Vibrocompaction projects undertaken in the UAE are on reclaimed Sands. These Sands which are predominantly the crushable, calcareous, carbonate sands found locally as opposed to the more common quartz or silica sands that are featured in most design literature. The famous reclamations such as the iconic Palm Jumeirah in Dubai, often have specification for mitigation of liquefaction induced settlements, bearing capacity increases and total and differential settlement requirements. Often these performance targets are achieved by the means of achieving a particular relative density that are generally measured by a defined Cone Penetration Test, CPT targeting values of cone resistance (Qc), MPa at respective depth zones. In this paper some case studies are presented, where soil suitability for deep compaction by vibratory methods was firstly assessed for suitability using the Massarsch, 1991 compactability chart prior to the application of vibrocompaction and its subsequent evaluation. One such project named the Island Development required 17 to 23m depth of penetration only to treat the lower 5 to 6m of sand above rockhead as eventually the top 15m of sand will be further excavated to allow for the construction of basement. The paper will present pre and post CPT results, the results of initial site calibration trials and evaluation of the completed works.

Oct 1, 2022

By Ronnie X. Gu, Xing Zheng, Gem-Yeu Ma

Due to implementation of the rotator construction method from which a smooth shaft was anticipated, a full-scale pile load test (Osterberg Method) was performed at Pier 14 Pile 9 of the main span of the New Benicia-Martinez Bridge to confirm the design parameters of the rock sockets. Two levels of load cells were fabricated in the reinforced cage of the rock socket. Each level consisted of three 670-mm Osterberg load cells with a total testing capacity of more than 50 MN in both directions. In an attempt to separate side friction and end beari ng, a 75 mm thick compressible Styrofoam material was placed at the bottom of the cage. The pile load test was carried out in four stages. The multi-level multi stage pile load test data was interpreted for casing friction, side friction for two rock strata, end bearing, and residual side shear values under repeated loading in opposite directions. The side friction from the casing in soils at Stage 2 is approximately 9 MN. The end bearing at the tip of the rock socket at Stage 3 was calculated to be approximately 17 MN at a displacement of about 75 mm. The residual side shear resistance for the 10 m 50% RQD rock strata was calculated to be 9 MN or approximately 50% of initial values, after being pushed 0.3 mm upward in Stage 1, 71 mm downward in Stage 2, then 55.5 mm upward again in Stage 3, and finally 105.3 mm downward in Stage 4. The test results surprising ly indicate that the side shear resistances from both low RQD intensely weathered rock and higher RQD slightly weathered competent rock are about the same at approximately 19 MN. This pile load test provides very critical information for confirming deep shaft design and analyses.

Jan 1, 2005

By Lois G. Schwarz

I did a project (Sungai Piah) as a consultant to your firm in Malaysia, where we were faced with a similar situation as sketched out in your question. The following is what we did for the grouting of the primary holes, which were both located upstream of the plug as well as downstream: We used a hydrophobic MDI based semi-rigid polyurethane prepolymer in the first phase of the grouting operation when grouting under water flow conditions. Then in the second phase and also for the contact grouting we used a two component water compatible polyurethane elastomer. And then for deeper formation grouting, when all the water flow had been stemmed in the vicinity of the plug, we used a regular (balanced stable) cement based grout. So it may not exactly answer your question, but we first used hydrophobic grout because it is very efficient to grout a formation through which water flows. We didn't stop all the leaks day-lighting downstream of the plug or all water running through the formation near the plug, but the flow of water through the rock formation adjacent to the plug was reduced by 99.9%, after completing the urethane grouting. This facilitated the placement of cement based suspension grouts without wash-out.

Feb 10, 2003

By Ke Yang

"Drilled shafts are typically used to support structures subjected to large moments at the shaft head. The large moment can produce push and pull forces on the two sides of a drilled shaft. Consequently, the applied moment is partially resisted by the push-pull moment resistance induced from the vertical side shears. This type of push-pull resistance has not been fully recognized in most design and analysis methods. In this paper, a 30 finite element model for a drilled shaft subjected to lateral load and moment is presented and is validated against two field lateral load tests. Based on the 30 finite element model, a parametric study is carried out. It shows that the push-pull moment can resist 18-35% of the applied moment. The parametric study also shows that the push-pull resistance varies linearly with loading eccentricity when the eccentricity is less than the shaft embedment length. A method to estimate the push-pull resistance is proposed based on the results of the parametric study. Then, a new method for lateral capacity prediction is proposed to account for the push-pull resistance. The base shear resistance is significant for short drilled shafts; therefore it is also included in the proposed method. A case study on four lateral load field tests illustrates that the new method could improve the accuracy of lateral capacity prediction when compared with the traditional Broms method.INTRODUCTIONDrilled shafts are typically used to support a variety of structures subjected to large moments. Sound walls, highway signs, traffic signals, high-rise buildings, electrical transmission towers, and bridge piers are examples of cases where lateral loads with large eccentricity would result in high overturning moments on foundations.Current analysis methods for capacity predictions (Broms, 1964a and 1964b; Brinch Hansen, 1961) or deflection predictions (Reese, et al. 197 4) of laterally loaded drilled shafts are based on the lateral resistance of soils and rocks. However, O'Neill pointed out that moments can be partially resisted through the push-pull resistance provided by the vertical side shears due to the rotation of the pile (Reese, 1997)."

Jan 1, 2005

By Christian Hoyme, Jochen Maurer

Most of the current foundation projects are suffering from disconnected information silos. In the first silo there is the planning of the project with corresponding data, presented by paper or digital drawings. Here will Building Information Modeling (BIM) be one of the trends for the future. We will see more and more projects leaving the “old way” of 2D drawings and moving into 3D planning including metadata of the foundations. But even with a perfect BIM model of a jobsite, we are not at final end of digitalization. While execution of the project at the jobsite, a second data silo is evolving. Data collected directly from construction equipment and manual measurements is currently undervalued in most projects. Paper is passed to the equipment operator and major data from measurements on site are noted on paper and digitized afterwards. Automatically collected data is not be used to create site progress reports or similar report. So, the real “data” just flows around without connection to any other data already existing in projects. And then the third silo arises: The documentation of the project. Data collected on paper es reentered to create some basic documentation of the work handed over to the client. Spreadsheet software is still the “tool-to-be-used” to create at least some documentation. Finally, the documentation is not connected to the data created while planning and not connected to the automatically collected data from the jobsite. A connected jobsite in the foundation industry must link these information silos and have to create a full data-workflow from the design through the execution to the as-built documentation. INTRODUCTION Building information modelling (BIM) is currently the most popular term of construction business in Germany and probably all over the world. But as often there are many different definitions out there and everyone has his own definition or at least understanding what BIM is about. But for sure it is the most relevant for the construction industry in the near future. Most popular is the digital twin for the upper structure of a building. In most cases the BIM models just shows the building itself, but there is more to be implemented. For example: projects where a special foundation is needed, BIM should include also the foundation elements with meta data. There are several advantages. Not only the clash detection of anchors, but also the possibilities to check the interaction with neighbor constructions, power lines and so on are a use case. For sure most of the special foundation elements are not relevant for the whole lifecycle of a building. But during construction and later the demolition the information about the hidden elements is important and gives a benefit to all stakeholders. In the future there will be not the question: “What is already in the ground?”. The risk for following construction projects on the same ground will be minimized.

Jan 1, 2019

By A. Bozorgzadeh, B. M. Jensen, B. N. Koelling, B. R. Murtaugh

"The Service Base mooring system originally consisted of two general types of structures, 19 timber piles cabled together and steel three-legged pipe piles. The St. Louis District fleet moored to the fleet barges which were tied off to shore-side concrete deadman and supported on the landward side by the timber and steel piles. The purpose of this project was to replace the existing floating wharf mooring system at the St. Louis Service Base. The Marine Design Center of the U.S. Corps of Engineers developed a three pile cluster system concept. The clusters consisted of one vertical pile and two batter piles. Piles in rock sockets were selected to resist the uplift loads due to high wind loads on the tall, spare lock gates stored at the floating wharf. This paper focuses on the design of the rock sockets for steel pipe piles with large uplift loads and the lessons learned during the design and construction of this system.INTRODUCTIONBackgroundThe U.S. Army Corps of Engineers’ St. Louis District is located at the critical transition point on the Mississippi River where it is a “locking river” north of St. Louis and an “open river” to the south. The St. Louis District is responsible for maintaining navigation channels on the Mississippi River, the Illinois River and the Kaskaskia River. It is also responsible for the operation and maintenance of five locks and dams within its geographic boundaries.The St. Louis District utilizes a fleet of vessels (dredges, crane barges, motor vessels, and barges) to support the navigation mission identified above. The St. Louis District Service Base, located in St. Louis, Missouri, serves as the base of operations for the district fleet. This riverfront facility originally consisted of a floating wharf, a railroad trestle, and a walkway down the river bank to the floating wharf. Historically, there have been two fleeting areas at the Service Base. The main fleeting area was approximately 965 feet long and consisted of six fleet barges (Figure 1). This area supported the Dredge Potter and its attendant fleet. The upper fleeting area was approximately 1,050 feet long and consisted of various stop log, crane and work barges, dredge pipe pontoons and work flats."

Jan 1, 2017

By Eric S. Lindquist, Charles A. Luxford

The State of Texas recently adopted a master plan to expand the existing Capitol Complex in Austin. Phase 1 of this expansion will add two new State office buildings and five levels of underground parking to the existing Complex. Additionally, a landscaped pedestrian mall will be built atop a portion of the underground parking to enhance the area as a cultural destination. Capitol Complex website: https://www.tfc-ccp.org/ Brierley Associates was selected to provide detailed design of the entire Phase 1 earth retention system for an approximately 40-65 ft (12-20 m) deep, 500,000+ yd3 (380,000+ m3) excavation through overburden soils and limestone bedrock. To facilitate overall project coordination, all design packages were required to develop Revit models, including the retention system package. With the project located in an urban setting, this 3D model also facilitated coordination of the retention system with adjacent major structures and utilities. The retention system is a combination of soil nails, soldier piling with tiebacks and rock anchors with a shotcrete facing as a substrate for the below-grade blindside waterproofing system. Due to the substantial scope of excavation, a significant number of utilities had to be routed on a temporary span over the excavation. Brierley Associates designed this utility support structure, which required extensive coordination with the excavation support and existing utilities located directly underneath the structure’s foundations. Preconstruction geotechnical work identified a fault zone that might be encountered within the excavation; however, the fault feature was found to have a more adverse location and orientation than originally anticipated. This observation required that a portion of the temporary anchors be converted to higher-capacity, corrosion-protected permanent anchors.

By Chandramohan P. V., Ravi Kishore

"An underground reservoir was to be constructed at Doha in Qatar. Simsima lime stone is present at the bottom. When the reservoir is empty, there will be uplift at the bottom but this will change to downward load when it is full. The rock at the bottom had high bearing capacity to resist downward load. But uplift had to be resisted by piles or anchors. The reservoir has a size of 120mx80m. Shrinkage and creep of concrete coupled with thermal contraction imposed a horizontal movement of 26mm on the extreme piles. So, piles have to accommodate this as well. This unique situation needed a unique solution. The solution was to provide piles with flexible high tensile strands to take tension. An annular space near the head of the pile would facilitate horizontal movement as well. Compression load was directly passed on to the raft bearing on rock.INTRODUCTIONAn underground reservoir for storage of drinking water was to be constructed at Doha, Qatar. The reservoir was proposed to have a plan size of 120m x 80m. Clear height inside the reservoir was proposed as 17.2m, from the bottom of roof to the top of bottom raft. Overall height of the reservoir at the outlet from the top of the roof to the bottom of raft was to be 21.2m. For the sake of inspection and in order to prevent pollution from the surroundings a gallery was planned around the reservoir. This could accommodate pipelines as well. This gallery was 3.0m wide on three sides and 8.4m wide on the outlet side.The gallery had removable gratings as cover in order to facilitate maintenance. Capacity of the reservoirwas proposed to be 40million gallons. The reservoir is divided into four compartments with baffle walls in each one for water circulation. Roof of the reservoir is kept at 300mm above ground level. There are two levels of car park on top of the reservoir. Top of the reservoir roof is at +14.35. Bottom varies from - 6.68 to -7.08. Lowest water table is at +6.00. Concrete structure of the reservoir was designed by a local consultant. The Navayuga Engineering Company was entrusted with the construction. Please see Figs 1 and 2."

Jan 1, 2017